<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        .big {
            width: 100%;
            height: 30px;

        }

        .item {
            width: 15%;
            height: 30px;

            float: left;
            /* 左浮动 */
            margin-left: 5px;
            margin-right: 5px;
            text-align: center;
            line-height: 30px;

        }
    </style>
</head>

<body>
    <!-- 大盒子 -->
    <div class="big">
        <div class="item">首页</div>
        <div class="item">图片</div>
        <div class="item">贴吧</div>
        <div class="item">看看</div>
        <div class="item">登录</div>
        <div class="item">注册</div>
    </div>
</body>

</html>